Toronto Raptors guard Kyle Lowry will undergo surgery that could sideline him for the rest of the regular season.

The Raptors posted the news on Twitter on Monday, saying he was scheduled for surgery Tuesday morning "to remove loose bodies from right wrist. Aim to return for playoffs."

Sources tell The Vertical's Adrian Wojnarowski that Lowry could return in four-to-five weeks.

Lowry injured the wrist in Toronto's game versus Charlotte on Feb. 15, but played in the NBA all-star game four days later in New Orleans plus participated in the three-point shooting contest. He said he hadn't thought the injury was serious. He received treatment from the Pelicans staff in New Orleans, and had the wrist bandaged with ice when he wasn't on the floor.

The news comes as a surprise a day after coach Dwane Casey had said tests showed no significant damage to Lowry's wrist.

Team president Masai Ujiri was scheduled to address the injury in a conference call with media later Monday.

With 23 games left in the regular season, it's also a big blow to a team looking to climb back up the Eastern Conference standings. Lowry is second on the team with his average of 22.8 points and leads the Raptors with 6.9 assists per game. The Raptors have averaged 113.2 points with Lowry on the floor this season, compared to 105.1 without him. Defensively, they've allowed 105.1 points with Lowry in the game versus 108.6 without him.

Cory Joseph and Delon Wright fared well in Lowry's absence in Sunday's 102-96 win over Portland. Joseph had 14 points and six assists, while Wright added 11 points.

The Raptors, who are fourth in the Eastern Conference, took a three-game winning streak into Monday's game against the Knicks in New York. They face Eastern Conference rival Washington Wizards, who are ahead of the Raptors in the standings because of a slightly better winning percentage, in back-to-back games later this week.